Everything about Illarion that fits nowhere else. / Alles über Illarion was inhaltlich in kein anderes Board passt.
I think that should answer your question about the format.Last but not least the possibility of play OGG Vorbis files was added to the client. Those are the open source equivalent to MP3 soundfiles and offer us the possibility to add more soundfiles to the client without a large increase to the size of the files. Also these new ogg files are played faster and with less hardware ressources than the old wav files.